Sensitive switch actuator



Feb, 1949. M. M. HENNESSY SENSITIVE SWITCH ACTUATOR Filed Aug. 51, 1946 v mmvroza. 27 777% W A T'TORA/E/i Patented Feb. 1 1 949 UNITED STATES PATENT OFFICE SENSITIVE SWITCHi ACTUATQR Mark M. Hennessy, Milwaukee, Wis, assigfnor to Durant Manufacturing 00., Milwaukee, Wis., a.

corporation of Wisconsin Application August 31, 1946, Serial-No. 694,224.

(Cl. M -96) 4 Claims.

The present inventionrelates in general to improved mechanism for transmitting motion fromv one article or element to another, and relates more specifically to an improved assemblage for effecting periodic actuation of relatively frail and sensitive electric switches or the like.

The principal object of my invention is to provide an improved actuatorfor relatively. frail. and sensitive electric switches and the like, which is simple and durable in construction and reliable in operation, and which is moreover flexible in its adaptations.

W'hen utilizing sensitive snap-action electric switches of' the type wherein the movable con.- tact is carried by a spring metal arm and is snapped from one limiting position into another by means of one or more integral cantilever leaf springs when plunger pressure is applied to the carrier arm near its anchored end, it is frequently imperative that the push button or actuating plunger be quickly and positively pressed.

and released. This is especially. true when such switches are used to control the operation of counters for registering a succession of moving articles, machine performances, or other events, and in such cases the mechanism for actuating the switch operating plunger must not only be positive in action and susceptible of adjustment to meet varying conditions, but it must also be adapted for actuation with a relatively light touch in cases where the movements or articles being counted are too light to, actuate a mechanical counter direct. The switch actuating mechanism must also be effectively operable while disposed in any position, and should be applicable in cases where overtravel or time elements are required after each performance of a machine or happening of an event.

It is therefore a more specific object of the present invention to provide an improved actuating device for sensitive electrical snap switches or the like, which meets all of the above mentioned requirements and conditions, and which is adapted to be utilized for diverse purposes.

Another specific object of this invention is to provide an improved motion transmitter for transferring periodic or successive movements of a machine or series of articles to a control device such as a snap switch, in a most effective manner and with the exertion of minimum effort.

,A further specific object of the invention is to provide an improved sensitive switch actuator which may be operated in any desired position, and which will also automatically compensate for overtravel or time elements involved in the operation of the deviceswith which the actuator is associated;

Still another spe ific object of my invention is to provide simplified mechanism for imparting successive clear-cut and distinct operating move.- ments to the push button or actuating plunger of a snap actuated element such as an electric switch contact carrier arm or the like, which vantages of the improvement willbe apparent from the following detailed description,

A clear conception of the features constituting my present invention, and of h ode of constructing and utilizing a typical embodiment thereof, may be had by referring to the drawing accompanying and for'minga part of this specification in whlch'like reference characters designate the same or similar parts in the various views,

'Fig. 1 is a fr ont view of a typical snap switch actuating mechanism, having a portion of the closure cover broken away'and showing the actuati'ng arm in neutral or inactive position;

Fig, 2 is a transverse section throu hthe as? semblage of Fi 1 taken along theirregular, line 2. 2. and looking in the direction of the. arrows;

and

Fig. 3 isan enlarged part sectional fragmentary.

view of the upper portion of the actuator; show.-

ing the operating arm in action in both solid and dot-and-d'ash lines.

While the invention has been shown and ,de;

scribed as being advantageously applicable tolsenf sitive electricsnap switches of a particular type;

it not my desire or ntent o -to n e ssar y l t t e Scope or to restri t e u li y o t m; proved features by virtue of this specific embo.di.- ment.

Referring to the drawing, the improvedswitch actuating assemblage shown therein, comprises in. general a main housing'or casing. 5 havingv a, re

movable closure cover 5; a sensitive snap switch I' mounted centrally within the casing .5 and. be.-

ing provided with a movable contact, carrier arm. 8. and with a push button or plunger 9. for apply= j ing actuating pressure to the arm 8; a leaf spring I!) anchoredat one end to the switch housing and 7 having its medial portion coopera'ble with the switch plunger 9 while its opposite end I I is freely swingable; a rigid lever l2 swingable about a fixed pivot pin l4 and coacting remote from this pivot r with the leaf spring .end i I and with one end of a helical compression spring the opposite end of which isconfinedwith a socket l6 formed in the main casing 5; an oscillatory shaft I1 journalled in a bearing l8 formed in the casing 5 and having its inner end provided with a transverseislot or; recess H] the flat bottom surface of which is I adapted to coact with the adjacent flat surface of the lever l2, while its outer end projects outwardly of the casing 5 and has a collar 2| clamped thereto by a set screw 22; and an operating lever arm 24 adjustably associated with the collar 2| and shaft l1.

The main casing 5 may beprovided with sup,

porting lugs 25 and'with an opening 26"for ac commodating the electrical currenticonducto'r's' for the switch Land the closure cover Bis detachably secured to the casing by screws 21. The snap switch! which, is fastened Within the'main casing 5 by means of screws 28, is of a well known ypelhaving the contact carrier arm B forthe' movable contact 29 anchored to the switch base near the push button or plunger 9, so that'slight pressure applied to the protrudingflend'of'the plunger will cause the movabl'econtact' 29 to snap v from'one extremejposition ,tothe other, whereas parts of the-mechanism are of sturdy construction, they are relatively light in order to minimize the'efi'ects of gravity thereon.

When theimproved switch actuator has been properly constructed and assembled, it may be disposed in any desired position and utilized for diverse purposes, such as registering the count of an electrically actuated counter of articles which are too light and not sufllciently massive to actuate an ordinary' -mechanical counter. It

may also beutilized to'count asuccession of articles-such as bottlesycan's, jars, boxes and the like in commodity 'p acking'plants where remote registry of production is desired, .andin cases where sensitive limit switches are used to control releaseof the plunger will. automatically 'ca'u's'e the "contact 29 to return to'its initial'position.

The switch l is also provided with aremova'blel cap 30 for normally concealing the delicate parts thereof, and the leaf spring lfl which coacts with the plunger 9, may be held in proper positionby a pin 3| carried by a yoke 32 firmly secured to the switch cap 30' in any suitable manner.

. The lever l2 which is swingable upon the, fulcrum pin l4, ma'ybe formed of flat bar stock, and has plane parallel surfaces on its opposite sides, one of which is adapted to be slidably' engaged by the leaf spring end H, and the other of which is engageable with the fiat recess'surfac'e 26 whenever .the lever1I2 is in neutral position. The end of the lever l2 remote from the pivot'pin I4" is provided with notches 34 within which the adjacent end of the coil Spring l5 ,is seated, and the opposite end of this compression spring is seated within the socket l6 and is removably confined therein by means of the frame bearing 18, is prevented from shifting axially by meansof inner and outer co'llars3'l', 33v

respectively, secured to the shaft by pins 39, 4D,"

and the inner pin 39. projects outwardly beyond theyperiphery of its collar 3'! and" is engageable with two stop pins 42, 43 secured to the casing 5 and disposed in the path of swing of 'the'protrudmg 'endofthepin as. y

The recess 19 formed in the .shaft' If! and through which the bar lever I2 extends'is preferably of suchwidth that the lever is fr eely movable therein, and -of'such depththatit extends As pre,

inwardly beyond the central shaft axis;

viously indicated, the bottom surface 20 of the recess 'l9isplane' and of considerable length so as to 'rather firmly and positively" hold the shaft I! in neutral positionwhen thesurfaceZO engages theLadjacent plane surface of thelever'l2, but the opposite ends of the recess surface 20 may be rounded 'as shown inorder to prevent excessive .wear on the shaft 11 and lever l2. The collar 2| a washer and a screw 3fi. 'I'hejoscillatory shaft I! which is'jour'nalled in various electrical functions requiring overtravel 'or time elementsin connection with machine operations, The arm '24 when in neutral position as shown in Fig. 1, permits the recess surface 20 to contact the'a'djacent plane surface of the lever l2 under the influence of the springs l0, l5; and whenever the arm2 l is swung in eitherdirection as shown in solid and dot-and-dash lines in Fig. 3, the cam portion of the shaft ll-atthe recess l9, will swing'the lever l2'towar'd theswitch 1 thereby compressing the coil spring l5 and operating the switch. Release of actuating'pressure on the arm 24, causes the springslfl; l 5 to quickly return thearm 24 to neutral position where it is retained bythe flat surface 20 of the recess l9,

and the protruding end of thepin 3 9 is engageable with: the stop pins'42', 43 so as to limit the oscillatory rnotion of the arm 24 in either direction.

- From. the fo fegoing detailed description, it

should be apparent that the present invention provides an improved 'actilator especially adapted for use" in'actuating sensitive electrical snap switches, which besides being light but durable in construction, is positive, in action. and is also flexible in its adaptations anduses'. The improved switch actuating mechanism is g operable with a verylight touch and many desired position, and the fiatsurface 26 of the pivot shaft ll cooperates with. the lever return spring Hi to insure rapid and automatic return of the arm 24 to neutral position whenever the latter is re- I leased. The arm 24 maybe swung in either direction, and adjusted to any desired length and to vari-eusfpositions along the shaft, H, so as to accommodate diiferent working conditions; and the pin 39 cooperating with the stoppinsq42, 43 prevents the shaft H from revolving completely about itsv axis 1 All of' th'e relatively light but strong parts of theassernblage are adequately protected against tampering andidamage by the housing casing 5,-but these enclosed parts are still readily accessible for inspectionand adj ustment.

The adjustable cscillatoryarm l 1 has also proven useful in compensating for overtravel and time elements existing or'requiredin connection with certain applications of the switch I', and oscillation of the lever 2Q ineither direction may either makeor break the. electric circuit, thus making the assemblagelexceeding'ly flexible in its adaptations. The improved snap switch actuator has proven highly satisfactory and successful in actual use, and may be manufactured at moderate cost in various sizes and for many different uses.

It should be understood that it is not desired to limit this invention to the exact details of construction or to the precise mode of operation and uses, herein shown and described, for various modifications within the scope of the appended claims may occur to persons skilled in the art; and specific terms used herein should also be given the broadest possible interpretation or meaning, consistent with the prior art.

I claim:

1. A switch actuator comprising, a switch housactuating plunger of the switch, the free end of said spring remote from said plunger slidably engaging one side of the swinging end of said lever, an oscillatory shaft journalled in said casing transversely of said lever and having a transverse recess provided with a flat elongated bottom surface facing and cooperable with the opposite side of the swinging end of said lever to position the latter in neutral position, said recess bein of greater depth than the length of the adjacent radius of the shaft, a stiffer second spring confined within said casing and coacting with said lever to constantly urge the same toward said shaft and recess bottom, and an arm projecting laterally of said shaft externally of said casing for oscillating the shaft.

2. A switch actuator comprising, a switch housing casing, a rigid lever pivotally suspended within said casing in spaced relation to the switch, a leaf spring interposed between said lever and the actuating plunger of the switch, the free end of said spring remote from said plunger slidably engaging one side of the swinging end of said lever, an oscillatory shaft journalled in said casing transversely of said lever and having a transverse recess provided with a flat elongated bottom surface facing and cooperablewith the opposite side of the swinging end of said lever to position the latter in neutral position, said recess being of greater depth than the length of the adjacent radius of the shaft, a stiffer second spring confined within said casing and coacting with said lever to constantly urge the same toward said shaft and recess bottom, an arm projecting laterally of said shaft externally of said casing for oscillating the shaft, and means for effecting adjustment of said arm along said shaft and for varying the length of the arm.

3. A switch actuator comprising, a switch housing casing, a rigid lever pivotally suspended within said casing in spaced relation to the switch, a leaf spring interposed between said lever and the actuating plunger of the switch, the free end of said spring remote from said plunger slidably engaging one side of the swinging end of said lever,

an oscillatory shaft journalled in said casing transversely of said lever and having a transverse recess provided with a flat elongated bottom surface facing and cooperable with the opposite side of the swinging end of said lever to position the latter in neutral position, said recess being of greater depth than the length of the adjacent radius of the shaft, a stirl'er second spring confined within said casing and coacting with said lever to constantly urge thev same toward said shaft and recess bottom, an arm projecting laterally of said shaft externally of said casing for oscillating the shaft, and means within said casing for limiting the oscillatory movement and for preventing axial displacement of said shaft.

4. A switch actuator comprising, a switch housing casing, a rigid lever pivotally suspended within said casing in spaced relation to the switch, a leaf spring interposed between said lever and the actuating plunger of the switch, the free end of said spring remote from said plunger slidably engaging one side of the swinging end of said lever, an oscillatory shaft journalled in said casing transversely of said lever and having a transverse reoess provided with a fiat elongated bottom surface facing and cooperable with the opposite side of the swinging end of said lever to position the latter in neutral position, said recess being of greater depth than the length of the adjacent radius of the shaft, a stiffer second spring confined within said casing and coacting with said lever to constantly urge the same toward said shaft and recess bottom, an arm projecting laterally of said shaft externally of said casing for oscillating the shaft, a collar secured to said shaft within said casing by a pin projecting beyond the collar for preventing axial shifting of the shaft, and stop pins cooperable with said projecting pin to limit the oscillatory movement of said shaft.

MARK M. HENNESSY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,289,108 Eaton July 7, 1942 2,328,266 Durbin "Aug. 31, 1943 2,331,997 Mensenkamp Oct. 19, 1943 2,336,425 Shouton Dec. '7, 1943 2,355,457 Mares Aug. 8, 1944 2,413,130 Aitken Dec. 24, 1946 

